


a strict progression of cause to effect

by JenTheSweetie



Series: a strict progression of cause to effect [1]
Category: Sherlock (TV)
Genre: Blow Jobs, Crack, M/M, Time Travel, somehow the two of those go together
Language: English
Status: Completed
Published: 2017-09-19
Updated: 2017-09-19
Packaged: 2018-12-31 15:47:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,486
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12135762
Author URL: https://archiveofourown.org/users/JenTheSweetie/pseuds/JenTheSweetie
Summary: "Do try not to create any paradoxes.  The paperwork I'd need to invent would be tiresome."Sherlock learns a little something about sex.  And the causal nature of reality.  But mostly sex.





	a strict progression of cause to effect

**Author's Note:**

> Thanks to Snapjack for the prompt and the cheerleading. Title lifted from everyone's favorite Doctor Who quote.

"It won't work," Sherlock said.

"Of course it won't," Mycroft said.

"The physics don't make any sense."

"It would never be able to move fast enough."

"Or with enough precision."

"And even if it worked, it would be highly dangerous."

"Quite possibly lethal."

They both stared at the time machine.

"I want to try it anyway," Sherlock said.

"Yes, I assumed you would," Mycroft said wearily.  "One year into the future, perhaps?"

"Yes, that should do nicely," Sherlock said.

Mycroft typed in a date.  "Do try not to create any paradoxes.  The paperwork I'd need to invent would be tiresome."

"I'll bring back intel from your future self to make up for it," Sherlock said, stepping into the machine.  

"Don't forget about the causal nature of reality," Mycroft said, and Sherlock rolled his eyes.

And woke up... in his own bed.

The door creaked open, and Sherlock rolled over to see John shutting it behind him.  "Oh," John said, sounding surprised.  "When did you get home?"

"Recently," Sherlock said.  "Did Mycroft - "

The rest of the sentence died on his lips, because John... had just taken off his shirt and dropped it on the floor.  

Sherlock stared at him.

"Did Mycroft..." John prompted, unbuckling his belt.

"Did," Sherlock began, "um - "

"What's all the blinking about?" John said as his trousers dropped to his ankles.

"Nothing," Sherlock said.

John lifted up the blanket and slid into bed next to him.  "Right," he said, flopping down on the pillow next to Sherlock's.  "Hello."

"Hello," Sherlock said.  He scanned through his deductions, crossing off possibilities until he determined that either John was drunk, or Sherlock really had time traveled into a future in which he and John were -

John leaned forward and pressed his lips to Sherlock's.

Right.  So.  The second one, then.

"Rosie's asleep," John murmured against his lips, crowding up closer to Sherlock and wrapping an arm around his waist.

"Right," Sherlock choked.

John sucked on his lower lip and splayed his fingers out on Sherlock's back, the tip of his pinky dipping under the waistband of Sherlock's trousers.  Sherlock jerked forward in surprise.

"I thought you'd be out late," John said, sliding his entire hand into Sherlock's pants and squeezing his arse.  "This is a nice surprise."

"Hnnnnn," Sherlock replied, because there was something very, very hard pressing against his stomach and it definitely was _not_ John's gun.

"A much nicer surprise than the worms in the sink this afternoon," John continued, pressing kisses along Sherlock's jaw.  "Nearly makes up for that surprise, in fact."  He slid his hand away from Sherlock's arse and made quick work of Sherlock's trousers and then his pants, pushing them down to his knees, his fingers barely grazing Sherlock's rapidly stiffening cock.

"John," Sherlock gasped. "I - "

"Mmm?" John said, his fingers doing another teasing sweep.  "Sorry, were you saying something?"

"Ah," Sherlock said, his hips thrusting forward automatically, "you - "

"I was thinking about this all day," John said, finally wrapping his hand around Sherlock's cock.  He stroked him gently, his thumb pressing against the head, and Sherlock let his head fall back.

That was a mistake; John took the opportunity to bite  Sherlock's neck, and Sherlock groaned loudly.  He had to tell John to stop, he was _going_ to tell John to stop, in just a moment he was going to stop him and explain that he was from the past and -

"You know, I think I want you in my mouth," John murmured into his ear, and Sherlock choked on nothing.  

"Nnnfff," he said as John gave his cock one last stroke and then slid down his body.  He kissed his collarbone and then took a pebbled nipple into his mouth - Sherlock jumped as he swept a tongue over it, and John chuckled and kept moving down, mouthing over Sherlock's stomach and then pushing Sherlock onto his back, crawling between Sherlock's legs.

"John," Sherlock said, staring at the ceiling as John situated himself at the bottom of the bed, "you should know that - "

And that's when John took the head of Sherlock's cock into his mouth.

He had time traveled into a future where John put his mouth on Sherlock's cock; he wasn't sure which half of the sentence was more surprising.  

John's tongue curled around the head of Sherlock's cock, and Sherlock grasped at the sheet, willing his hips not to buck.  John took him in deeper, his hand coming up to fondle Sherlock's balls, and Sherlock bit down hard on his lower lip.    

"John," he said, "wait."

John pulled off with a wet _pop_.   His lips were shiny with spit.  "Everything okay?"

"Um," Sherlock said, "yes."

"Good," John said, and ducked his head again.

Sherlock groaned and put his fist to his mouth; between John's mouth and his hand and oh, god, his _other_ hand, this wasn't going to last long. Sherlock tried desperately to think of how to say _Where I come from we don't do this as a general rule_ without ruining the moment, and found that it was pretty much impossible.

Speaking of impossible: _thinking_ was growing increasingly difficult as John moved faster and faster, humming a little around the head of Sherlock's cock.  Sherlock pressed his lips together, and John pulled off once more, licking his way from the root to the tip, said, "You don't have to be quiet, Rosie's fast asleep - god, you know how I like to hear you - " and then took Sherlock in as deep as he could.

Sherlock let out something between a groan and a wail, and John groaned along with him.  His hand was moving in time with his mouth, and his tongue was twisting around Sherlock's head.  "I'm," Sherlock gasped, "I'm going to - "

And then he did, rather spectacularly, straight down John's throat; Sherlock could feel him _swallowing_.    

John crawled up the bed until he was hovering over Sherlock's head and kissed him, the taste deeply unfamiliar and even more deeply erotic.  His hand was moving between his legs and Sherlock realized, a bit belatedly, that that was, it seemed, something _he_ should be doing; he reached between them and John groaned in relief as he wrapped his hand around John's cock, his own twitching weakly in sympathy.

"God, you're so," John said, his breath hot against Sherlock's mouth, "oh god, _yes_ \- "

"How should I," Sherlock began, but John cut him off with his mouth, his tongue slipping between Sherlock's lips and his hips rutting against him. Sherlock was fairly certain he was terrible at this, but John either didn't notice or didn't mind; he thrust into the circle of Sherlock's hand, threading his hand into Sherlock's hair and pulling hard enough to hurt in the very best way.

"Fuck, Sherlock," John said.  "Faster, _yes_ \- "

Sherlock was nothing if not observant, and soon the pace of John's thrusts picked up and he pressed his mouth to Sherlock's and went silent, his hips stuttering and then slowing as he spurted all over Sherlock's stomach.  

John pressed his face to Sherlock's neck and kissed him, their sweat mingling.  "Now," he said, "what was it you were going to say before I got distracted?"

Sherlock swallowed.  “Nothing, really.  It’s just - have I ever mentioned - ah - time travel?"

John went still.  "Oh, you've got to be kidding me."

"Apparently I have," Sherlock said.

“You got in a time machine just now.”

“Yes.”

" _This_ is that?  This?  Right now?"

"Er," Sherlock said, "yes."

"And you came from before you and I started doing, you know, things like _that_?"

"Yes, definitely," Sherlock confirmed.

"Oh my god," John said.  "Why didn't you stop me?"  

He sat up and glared at Sherlock in the moonlight, which was slightly less intimidating than it would have been had he been wearing any clothes.

"Well," Sherlock said, "the thing is, you started, ah, doing _that_ , and I'm not exactly experienced at stopping you from - well, I'm not exactly experienced at _any_ part of - "

"Hang on _,_ " John said.  "That was your first time _?_ "

"In some senses of the word, yes," Sherlock said, "and in other senses of the word... also yes."

"When the other you gets back," John said, "I'm going to kill him."

"So what you're saying," Sherlock said, "is that I _didn't_ tell you exactly what happened when I time traveled. "

"You said you 'found something out that seemed to indicate that our relationship had changed'," John snapped.  "You didn't mention the _blow job,_ you absolute _tosser."_

"Well, now that you've told me what I said, it's _your_ fault," Sherlock said reasonably.  "That's how causality works."

"Oh, no, don't you try to pin this on me," John said.  "You're the one who got into a _time machine_."

"It worked out for the best, _clearly_ ," Sherlock said defensively.  "I probably would have gone on thinking you _weren't gay_ like you're always claiming if you hadn't just had my _penis_ in your _mouth._ "

"Oh, piss off," John said.  

**Works inspired by this one:**

  * [Строгая последовательность причин и следствий](https://archiveofourown.org/works/14027925) by [never_v_hudo](https://archiveofourown.org/users/never_v_hudo/pseuds/never_v_hudo)




End file.
